Scope: Design and construction of two new 75,000 barrel (3.15 million gallon) capacity above ground jet fuel storage tanks
In 2015 Smithbridge undertook the design and construction of two new 75,000 barrel (3.15 million gallon) capacity above ground jet fuel storage tanks at Cabras Distribution Terminal for IP&E.
The project was undertaken in a complex working environment within the live operational fuel terminal receiving, storing and distributing a range of petroleum products. This required mitigation of the risks associated with performing hot construction work within the live terminal. Furthermore, Smithbridge had to ensure we could safely erect large tank structures throughout the project, considering Guam’s typhoon prone environment.
Smithbridge executed a full design and build scope of work, including:
- Supply, fabrication and installation of a two new 75,000 barrel capacity jet fuel storage tanks
- 10,000CY+ of excavation and earthwork
- 5,000CY+ of reinforced concrete construction
- 7,000LF+ of fuel pipeline construction
- Electrical tank gauging and pump start systems
- Fire protection in accordance with NFPA standards
Innovative tank jacking system
Smithbridge adopted an ingenious method of tank jacking, which featured 10 jacks around the perimeter of the tank. The tank jacking system had the ability to lower the partially erected tank onto the permanent foundation for rapid and safe securing in the case of a typhoon. Conventional bottom up tank construction methods are far less structurally sound and more susceptible to failure in high wind events. Our method proved invaluable when Guam was put into typhoon Condition of Readiness 1 state on several occasions. These passing weather systems provided plenty of production challenges on site, particularly welding between heavy periods of sustained rain. By project end, the construction team became well drilled and skilled in securing the safety of the project work site and adjacent infrastructure.
In addition, the jacking system enabled the majority of the tank assembly and welding work to take place at ground level or slightly above (<6’) eliminating some working from heights.
Value Engineering Solution with Precast Concrete
Smithbridge proposed a value engineering solution to IP&E during the project, recommending a precast concrete wall design instead of an in-situ concrete wall design. This achieved significant schedule benefits in completing the concrete containment walls concurrent with the tank foundation. Additionally, the precast concrete wall design acted as a permanent vapor barrier between the existing fuel facility and new tank construction where “hot” steel welding work was due to take place – expediting the “hot” work phase of the project also.
Innovative Construction Improvements
Smithbridge suggested another innovative concept to IP&E in the early stages of the project, recommending the addition of a geotextile clay liner underneath the secondary containment system to improve the performance of the system overall. IP&E again acted decisively and presented the idea to Guam Environmental Protection Agency for their endorsement and eventual approval. The geotextile clay liner provides an additional form of protection in the unexpected event of a major tank leak, a further back up to the original concrete secondary containment system proposed.
Excellent Safety Outcomes
Smithbridge achieved 98,000 person hours on the project without a lost time injury or accident – an achievement the entire project team are extremely proud of.